CMOS implementation of fuzzy analog circuitry: Technological error propagation over fuzzy output

Systems described by multiple variable and multiple parameter models having nonlinear coupling occur in fields of engineering, economy, etc. Predicting the behavior of such systems based on analytical techniques proved to be a very difficult approach. It turns out that in dealing with such systems, one has to face a high degree of uncertainty and tolerate imprecision. Soft computing, proposed by Prof. L.A. Zadeh, based on fuzzy logic, neural nets and probabilistic reasoning, has the characteristics of approximation and dispositionality. The tolerance for imprecision and uncertainty is used to achieve tractability, lower cost and economy of communication. As Fuzzy Logic is concerned with imprecision, it would be interesting to analyze how the fuzzy analog circuitry implementation technological errors can affect the fuzzy response of the system. We have chosen the field of CMOS analog circuitry which do not know so many implementations as digital fuzzy logic, and which, despite its elegance and compactness, is more prone to technological errors.